Here's a fun experiment: approach your common or garden gamer, and use the words "on," "rails" and "shooter" in quick succession. If your test subject immediately runs for the hills, they may have been scarred by Rebel Assault during their childhood. To an extent, it's an understandable reaction. At their worst, rail shooters are little more than digital carnival games. Blast the badguys that pop-up, then move along. Rinse, repeat, forget.

EA and Visceral Games must surely be aware of this negative perception of the genre, but if it bothers them they don't let it show. Dead Space Extraction is indeed an on-rails shooter, but one that bears all the hallmarks of being a top quality release. For a start, the graphics are excellent - far exceeding the low standards that blight so many Wii games. But beyond this, there's also a sense that the developers are trying to do something interesting with the genre. They want this game to be scary, to have an atmosphere that genuinely compares with the grim claustrophobia of the original Dead Space. It's an admirable goal, but is it one that Visceral can actually pull off?

On the basis of the build I played last week, they've certainly got a fighting chance. The demo was culled from the seventh of the game's 10 chapters, a section ominously entitled "Life and Death," with the player taking the role of the terrified Dr Helen Howell - one of four playable characters in the story. Our heroine is notable for two reasons: firstly, she's a woman of Indian ethnicity - a far cry from the stereotypical burly white space marine you tend to find in games like these. Secondly, she's losing her mind. Like Isaac Clarke in the original Dead Space, Dr Howell has been deeply affected by her traumatic experiences; as the player progresses through the ravaged mining colony of Aegis VII, you'll have to deal with the unpleasant visions she's suffering.

One of the many charming enemies

The demo begins with Dr Howell recording a video log recounting her adventures thus far - a clever conceit which allows the game to show the character's face. Towards the end of her entry, one of the monitors clearly shows a necromorph entering the room - but when the good doctor turns around, surprise surprise, there's no-one to be seen. The camera slowly prowls around the room, moving with a dread-inducing slowness. Suddenly we hear the sound of freaky chanting and the screen is filled with strange symbols, causing Dr Howell to collapse. When she picks herself up a moment later, the hidden beastie drops from the ceiling and attacks.

We've all seen this kind of device used in horror films a thousand times before, but that doesn't stop the moment from being extremely tense. It was a pleasant surprise to find pockets of fearful stillness cropping up amid the frenzied blasting; all the best survival games know how to mix loud and quiet scenes to good effect, but it's very rare to see such pacing in an on-rails shooter. In the moments between firefights, there were times when the game even recalled the likes of the first Alien film - a thoroughly commendable achievement, by any standards.

Such praise aside, most of the demo comprised of balls-to-the-wall shooting. After the first 'morph makes its appearance (and is summarily despatched) he's swiftly joined by several of his colleagues. Aside from looking wonderfully nasty in all their razor-armed glory, the animation on the mutants is also highly impressive - and the Wii seemed to have no trouble in showing several of the buggers on-screen at once. Most of the enemies in Extraction will be familiar to players of the first game, but apparently there'll be a few threats too. And as any Dead Space veteran will tell you, dismemberment is the key to destroying these nasties: slice or blow off their limbs, and turn them into bleeding beanbags.

Shoot its legs off!

In gameplay terms, the action is handled exactly as you'd expect: you aim with the Wii remote, fire with the B-trigger and tilt your controller to enable the alternate fire on your armament of choice. You can carry up to four weapons at any given time, using the Nunchuck thumb stick to flick between them. During your first run-through of the game you'll be limited to using weapons as your find them, but after you've completed a chapter you'll be able to unlock equipment so that you can go back and play through with a different loadout. Your default tool is the rivet gun - a weak firearm with unlimited ammo - but as you play through the level you'll stumble across familiar friends like the plasma cutter, line gun and ripper. I personally found the latter to be especially fun to use, stabbing at the screen in a wild effort to chop up every rotting freak in sight. Aside from the rivet gun every weapon in the game has limited ammunition, so you'll need to keep an eye on your reserves. A Gears of War-style meter allows you to speed up your reload times, but if you mess up the timing you'll leave yourself vulnerable for a few seconds.

In addition to your proper weapons, Extraction also allows you to perform a melee attack by waving the Nunchuck about. This is something of a last-ditch move, but at least it leaves a pretty light trail on the screen. Far more useful are your stasis and telekinesis modules. As in the last game, it's far easier to deal with multiple enemies if you freeze a few of them in place first - and this time around your stasis reserves automatically recharge over time, so you can afford to be fairly liberal with your attacks. Meanwhile your TK ability (mapped to the A button) is used to open lockers and crates, and to generally nab anything in sight. Your telekinesis grabber now resembles a sort of electrical yo-yo, and with two players competing for loot things can get quite hectic. While we're on the subject, the drop-in/out system seems to work flawlessly: if a mate decides to join you halfway through a chapter, they can join in at the touch of a button.

What isn't yet clear is how this co-op play will work with the game's story. The demo I tried was clearly based around the exploits of Dr Howell on her own, but supposedly the game will acknowledge the presence of two players. I certainly hope so, because there's a good chance that Extraction's plot will be a big part of the game's overall appeal. Halfway through the demo I encountered a "dementia moment" in which Dr Howell started to lose her tenuous slip on reality. As she moved down a corridor, sinister visions flashed on the screen and the soundtrack was filled with overlaid whispering. A busy press event isn't the best place to soak up a horror atmosphere, but I reckon that under the right circumstances the game could be quite unnerving. And on the basis of the cutscenes I've seen so far, the voice acting and motion capture work will also be of a very high standard.

There's still much to be seen of Extraction, particularly the welding and door-cracking mini-games that require players to solve simple puzzles while keeping hordes of nasties at bay. We've also yet to see what extent players will be able to choose their paths throughout levels. I'm told that each chapter will offer at least one fork in the road, but I suspect that the overall game will remain fairly linear. Such is the curse of the on-rails shooter.

All the same, there's a lot to like about the way Dead Space Extraction is shaping up. Towards the end of my hands-on time I battled a necromorph brute with the help of a fellow journalist. In the first stage of the fight we had to freeze the beast as he charged towards us, waiting until the last possible moment in order to gain the best possible angle of attack; as soon as he was frozen, we automatically flanked the boss so that we could unload in his weak spot. Eventually the monster started to gob balls of explosive venom at us, forcing us to use our TK powers to catch and return his projectiles. As we delivered the killing blow, the creature let out a gurgling moan and collapsed into a gooey slump. It was the most satisfying boss battle I've seen on the Wii in quite some time. If the full game can deliver more of the same kind of thrills without becoming repetitive, then Extraction should turn out to be a worthy sequel.

Dead Space: Extraction will be released on Wii on October 2